The international body in its report on Tuesday also stated in its Outlook that the Indian economy was "expected" to pick up at 7.0 percent next year.
The IMF had in April said India that would grow at 7.3 percent in 2019, however, three months later it projected a slower growth rate.
Only a couple of days ago, the World Bank had in its latest edition of the "South Asia Economic Focus" said that India's growth rate was projected to fall to 6 percent in 2019, from 6.9 percent of 2018.
The IMF further stated that the downward revision of India's growth rate compared to the April-2019 WEO of 1.2 percentage points for 2019, and 0.5 percentage point for 2020, reflected a "weaker-than-expected" outlook for domestic demand.
According to it, India's growth declined due to corporate and environmental regulatory uncertainty, besides concerns about the health of the non-banking financial sector, and weaknesses in automobile and retail sectors.
"India's economy decelerated further in the second quarter, held back by sector-specific weaknesses in the automobile sector and real estate as well as lingering uncertainty about the health of nonbank financial companies," said the IMF report.